Not all operators support color palette (especially the ones with tabs: Gradient, StaticParticles, etc.). I suggest making the color palette also available on double right click on any color field. The color palette to define color for the entire color variable.

it concern only operators where color is in an array. the color picker button is automaticly removed where param is in an array.
It's quite complicated to add the color picker button because it impact all layout organization and managment...
And to add double clik action to popup color picker it is not so easy too... and double click is actually use to reset values...
a pain in the ass.

So... No chance to unbind it from the other interface elements? Maybe make a copy of its code and make this copy a floating window just for array colors?
This way you won't have to affect array interface.

Alt+doubleclick will also be fine.

In fact, this feature is no big deal. As for me, I can well live without it. If it's too much pain, I will close this suggestion. What do you think?

yes it is always possible to find a solution, but for now I don't see an easy way to do that and I don't want to spend much time for this as it is not really a big deal . So suggestion closed for now (maybe later I find another solution).

Anyway, thanks for the investigation.